As mentioned previously, rings were typically made using leftover components from earrings, small pins, and necklace/bracelet sections. Most were made with adjustable bands, so it is easy to size them.
As I’ve included a cameo ring, this would be a good time to mention that Florenza used hand-carved shell cameos for their jewelry designs. These were imported from Italy, and made Florenza jewelry of a higher quality than the glass and plastic cameos more typically used for costume designs. The pieces were sold with small tags imprinted “Genuine Cameo”.